JPH0310155Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a water jet propulsion boat suitable as a high-speed boat.

Conventional water jet propulsion vessels include those shown in Figures 1 to 3, in which Figure 1 is a longitudinal cross-sectional view showing its cruising condition, Figure 2 is a longitudinal sectional view showing its high-speed cruising condition, FIG. 3 is a longitudinal sectional view showing the state of navigation in waves.

As shown in Fig. 1, in this water jet propulsion ship, seawater is sucked in through an open water inlet 1 opened at the bottom of the ship, and an impeller 3 installed in a duct 1a.
be led to.

The seawater driven by the impeller 3 is jetted rearward as jet water from a water jet propulsion nozzle 1b provided at the stern, thereby propelling the water jet propulsion ship.

In addition, the code|symbol 2 in a figure shows the water surface, and 4 has shown the main engine which operates the impeller 3.

When the water surface 2 is calm, such a water jet propulsion boat enters a high-speed cruising state as shown in FIG. 2, and at that time, the boat body receives an upward force from the water surface 2 and rises to the surface. When such a hull floats, the resistance of the hull from the water is reduced, so that the required horsepower of the main engine 4 can be reduced.

However, in the above-mentioned conventional water jet propulsion boat, there is a risk that air above the water surface 2 will be sucked in from the open water intake port 1 as the boat floats up during high-speed cruising. When such an air suction phenomenon occurs, there are problems in that the efficiency of the impeller 3 is lowered and the main engine 4 is caused to fluctuate in load or overspeed.

In addition, as shown in Fig. 3, when this water jet propulsion vessel travels at high speed in waves, the hull movement due to the waves and the vertical movement of the water surface 2 overlap, causing the open water intake port 1 to drop to the water surface. It may appear above 2. In this state, the suction of water into the duct 1a stops, making it impossible to cruise at high speed and forcing the boat to decelerate.

The present invention is an attempt to solve the above-mentioned problems.The movable scoop member prevents air from being sucked in due to water absorption from the outside water inlet, while at the same time preventing the movable scoop member from protruding downward. By making the amount adjustable, the water jet can actively suck in water from below the bottom of the ship without causing air suction, making it possible to sail at high speeds even in waves. The purpose is to provide propulsion vessels.

Therefore, the water jet propulsion boat of the present invention has an external water suction section provided at the bottom of the ship, a duct that runs from the external water suction section through the inside of the ship to the stern, and a water jet connected to the rear end of the duct. The external water suction part includes a propulsion nozzle and a water-driving impeller installed in the duct, and the external water suction part has an opening formed in the bottom surface of the ship, and at least an upper end thereof is accommodated in the inner upper part of the opening. and a movable scoop member that can slide along the wall of the duct and protrude downward from the state, forming a water intake flow path leading from the water intake port of the movable scoop member to the duct. It is said that

Hereinafter, a water jet propulsion boat as an embodiment of the present invention will be explained with reference to the drawings. Fig. 4 is a longitudinal sectional view showing the main part of the first embodiment of the invention, and Fig. 5 is a view taken in the direction of - arrow in Fig. 4. 6 is a sectional view taken along the - arrow in FIG. 4, FIG. 7 is a vertical sectional view of the main part showing the protruding state of the movable scoop member in the second embodiment of the present invention, and FIG. FIG. 9 is a vertical cross-sectional view of a main part showing the retracted state of the movable scoop member in the second embodiment, and FIG. 9 is a cross-sectional view taken along the - arrow in FIG.

In a first embodiment of the present invention shown in FIGS. 4 to 6, an opening 1' is formed in the bottom surface of a water jet propulsion vessel.
A cylindrical guide portion 6 is provided that stands upright into the hull from the periphery of the opening 1'. Then, the movable scoop member 5 is guided by the cylindrical guide portion 6, and from a state where at least its upper end portion is accommodated in the inner upper part of the opening 1' in the bottom of the ship, the movable scoop member 5 slides along the wall portion of the duct 1a, which will be described later, and moves downward. It is provided so that it can protrude into the.

As shown in FIGS. 5 and 6, the horizontal cross section of the movable scoop member 5 is formed into a shape with as little resistance as possible. That is, the shape of the horizontal cross section of the lower part of the movable scoop member 5 is as shown in FIG.
The front part has a rectangular shape due to the water suction port 11a, but the rear part is formed into a streamlined shape.

The middle part of the movable scoop member 5 is a fifth
As shown in the figure, the upper part of the movable scoop member 5 has a standard horizontal cross section with the same external shape as the lower part, and the horizontal cross-sectional shape of the opening 1' and the outer cylinder 6 are formed in a streamlined shape. The upper part of the pipe is always slidably guided in a watertight manner.

The vertical movement of the movable scoop member 5 is remotely controlled by a drive mechanism (not shown).

Inside the movable scoop member 5, there is provided a water intake channel 7 that leads to a water suction port 11a formed on the front surface thereof. are fitted in a watertight and slidable manner.

That is, the water intake channel 7 and the duct 1a are connected smoothly and watertightly so as not to impair the vertical sliding movement of the movable scoop member 5.

Further, the water suction port 11a is provided with guide vanes 8 for rectifying and guiding seawater to the water flow path 7.

In this way, the external water suction section 11 is opened at the opening 1'.
and a movable scoop member 5, the external water suction part 11 is connected to a duct 1a inside the ship, the duct 1a passes through the inside of the ship and reaches the stern, and a water jet propulsion nozzle 1b is connected to its rear end. There is.

Further, a water-driving impeller 3 is provided within the duct 1a.

With the above-described configuration, when this water jet propulsion boat travels at high speed or in waves, the movable scoop member 5 is slid to protrude downward from the bottom of the ship. (See FIG. 4) This increases the submersion depth of the water suction port 11a and sufficiently prevents air from being sucked into the duct 1a.

Further, when the movable scoop member 5 is moved at high speed in a protruding state, it is possible to efficiently send outside water into the duct 1a by utilizing the speed of the water jet propulsion vessel relative to the water.

If there is no risk of inhaling air from the water suction port 11a while sailing, move the movable scoop member 5 along the wall of the duct 1a to reduce the resistance of the hull by moving the movable scoop member 5 into the ship by an appropriate amount. By adjusting the amount of downward protrusion of the movable scoop member 5 in this way, an increase in resistance during sailing can be avoided as much as possible while preventing air from being sucked in due to water absorption. It becomes possible to operate it.

In a second embodiment of the present invention shown in FIGS. 7 to 9, surrounding walls 16 are erected at the rear and side edges of the opening 1'' formed on the bottom surface of the ship.

The surrounding wall 16 forms a double wall that integrates the duct 1a inside the ship, and a swingable movable scoop member 15 that can be fitted into this double wall is supported by a horizontal rotating shaft 19 inside the ship, and a lever By being rotationally driven by a drive mechanism (not shown) via 20, it is arranged so that it can protrude downward from the bottom of the ship from a state where it is accommodated in the inner upper part of the opening 1'' in the bottom of the ship.

A water suction port 11'a is formed on the front surface of the movable scoop member 15, and a guide blade 18 is provided inside the water suction port 11'a for rectifying and scooping outside water.

In addition, the water intake channel 17 formed inside the movable scoop member 15 is connected to the inboard duct 1 leading to the opening 1''.
a, so that the inner wall of the water intake channel 17 can slide along the wall of the duct 1a, and in this way, the water intake channel 17 allows the movable scoop member 15 to swing reliably. It is set up so that it will not be damaged. The movable scoop member 15 and the opening 1'' constitute an external water intake section 11'.

Note that the nozzle 1b and the impeller 3 have substantially the same structure as in the first embodiment described above.

In the second embodiment of the present invention, with the above configuration,
As in the case of the first embodiment, the movable scoop member 5 is made to protrude downward from the bottom of the boat when the water jet propulsion boat is running at high speed or in waves.

This prevents air from flowing into the duct 1a, and at the same time, it is possible to use the speed of the water jet propulsion vessel against the water to forcefully send outside water into the duct 1a, unlike in the conventional case. Stoppage of water supply to the impeller can be prevented.

In addition, in this second embodiment, similarly to the first embodiment, if there is no risk of air inhalation from the water suction port 11a, the movable scoop member 5 can be retracted into the ship as appropriate. By adjusting the amount of downward protrusion of the movable scoop member 15, it is possible to perform an operation that prevents air intake due to water absorption while avoiding an increase in resistance during cruising as much as possible.

As described in detail above, according to the water jet propulsion boat of the present invention, there is an external water suction section provided at the bottom of the ship, a duct that runs from the external water suction section through the interior of the ship to the stern, and a rear end of the duct. A water jet propulsion nozzle connected to the duct and a water driving impeller installed in the duct are provided, and the external water suction part has an opening formed in the bottom surface of the ship, and at least an inner upper part of the opening. and a movable scoop member that can slide along the wall of the duct and protrude downward from a state where the upper end is housed, forming a water intake flow path leading from the water intake port of the movable scoop member to the duct. This simple structure prevents air from being sucked into the water jet propulsion duct even during high-speed cruising where the draft is shallow or when cruising in waves, thereby reducing efficiency due to impeller spin. In addition, there is an advantage that the movable scoop member can be appropriately retracted into the ship with reliable operation while continuing the water absorption action, and an increase in hull resistance can be reduced.

[Brief explanation of the drawing]

Figures 1 to 3 show a conventional water jet propulsion vessel. Figure 1 is a longitudinal sectional view showing its running state, Figure 2 is a longitudinal sectional view showing its high-speed running state, and Figure 3 is a longitudinal sectional view showing its high-speed running state. It is a longitudinal cross-sectional view showing the sailing state in waves,
Figures 4 to 9 show a water jet propulsion ship as an embodiment of the present invention. Figure 4 is a longitudinal sectional view showing the main part of the first embodiment of the present invention, and Figure 5 is the same as that of Figure 4. −
6 is a sectional view taken along the - arrow in FIG. 4; FIG. 7 is a vertical sectional view showing the main part of the movable scoop member in a protruding state in the second embodiment of the present invention; FIG. 9 is a vertical cross-sectional view of a main part showing the retracted state of the movable scoop member in the second embodiment, and FIG. 9 is a cross-sectional view taken along the - arrow in FIG. 8. 1', 1''...Opening, 1a...Duct, 1b...
Water jet propulsion nozzle, 2... water surface, 3... impeller, 4... main engine, 5... movable scoop member, 6... outer cylinder, 7... water intake channel, 8... guide vane, 11, 11'...Outside water suction part, 11a, 1
1'a... Water suction port, 15... Movable scoop member, 16... Surrounding wall, 17... Water intake channel, 18...
Guide vane, 19...Horizontal rotation axis, 20...Lever.

Claims (1)

[Scope of utility model registration request] An external water intake part provided on the bottom of the ship, a duct running from the external water intake part through the inside of the ship to the stern, and a water jet propulsion nozzle connected to the rear end of the duct,
A water-driving impeller installed in the duct is provided, and the outside water suction part is connected to the duct from an opening formed in the bottom surface and at least an upper end thereof accommodated in the inner upper part of the opening. A water jet comprising a movable scoop member that can slide along a wall and protrude downward, and a water intake flow path leading from the water intake port of the movable scoop member to the duct is formed. Propulsion ship.